Transitioning late-time cosmology with the Hubble parameterization

TL;DR

This paper models late-time cosmology within Rastall theory, using observational data to identify a transition from deceleration to acceleration and estimating the current Hubble parameter.

Contribution

It introduces a specific redshift transition in Rastall cosmology and constrains the Hubble parameter using multiple recent datasets.

Findings

Identifies a phase shift from deceleration to acceleration in the universe's evolution.

Estimates the current Hubble parameter as approximately 66.945 km/s/Mpc.

Demonstrates compatibility of the model with observational data.

Abstract

We investigate a late-time cosmological model for a homogeneous and isotropic space-time in the Rastall theory. We explore the observational constraints on the Hubble parameter by using the latest cosmological datasets such as cosmic microwave background radiation (Planck), baryon acoustic oscillations (DESI) and Type Ia Supernovae (Union 3.0). As a result, we explicitly demonstrate that the specific redshift transition occurs, namely, there happens a phase shift in the evolution of the universe from the initial deceleration era to the current accelerating phase of the cosmological scenario. Furthermore, we show that with the latest dataset of DESI-BAO clubbed with CC, CMB, and Union 3.0, the current value of the Hubble parameter is estimated as $H_0 = 66.945 \pm 1.094$, which can be compatible with the available observations.